And why would anyone buy a mac to try out an OS they don't even know much about. That's ridiculous.
You don't need to buy one, just go into an Apple store and the nice salesperson will be more then happy to demonstrate it to you.
Provided there's the right setup available. I've gone to computer stores and tooled around with Macs and I can think of only one that had Xcode installed. Give me one with Parallels/Visual Studio or Textmate.
Then the salesperson can bother off while I go for a test drive.